The 3×3 magic square is a grid which, when added up, totals the same number for any row or column or diagonal, filled with non-repeating numbers one through nine.

The modern game, however, that appears daily in most newspapers, originally called Number Place, was invented by an American architect, Howard Garns.

It was first published in the Dell Pencil Puzzle and Word Games in May, 1979.

It was renamed Sudoku in Japan, where it gained popularity in the mid-1980s.

Sudoku consists of nine 3×3 magic squares that must be solved so that each 9×9 row and column also use numbers one through nine only once and add up to the same number vertically, diagonally and horizontally.

That is, while you are solving each 3×3 square, you must make sure you are still conforming to the magic square rules for the whole 9×9 square.

Some numbers are supplied to get you started in each game.

The number of possible 9×9 Sudoku games is 6,670,903,752,021,072,936,960, or approximately 6.67 x 1021 or 6 sextillion variations.

You’re funny, Grandma KC. I was intrigued at how many possible combinations there are, so it can play out in a nearly infinite variety for people to get into the habit with. Love that your granddaughter enjoys it!

I LOVE Sudoku! Play it every day, but only the 4 or 5 starred games since I’ve become fairly proficient at it. It is said that “older people” (who me?) should exercise their brains with puzzles to fend off senility. I agree with that and this game is one of my choices.
Thanks for digging up all the info on its origin. Your site is such a treasure trove of enrichment for my grandkids when they become old enough to learn while having fun with grandma!